package Java5;

import java.util.Scanner;

public class Find{
    public static void main(String[] args){
        int[] arr = {1,2,3,4,5,6,7,8,9};
        int left = 0;
        int right = arr.length-1;
        Scanner scan = new Scanner(System.in);
        int a = scan.nextInt();
        while (left<=right)
        {
            int mid = (right+left)/2;
            if(arr[mid]<a) {
                left = mid + 1;

            }else if(arr[mid]>a){
                right = mid-1;
        }else if(arr[mid]==a){
            System.out.println("找到了！");
            break;
        } else{
                System.out.println("不存在！");
                break;
        }

        }
    }
}